Method of making brazed joints.



PATENTED JULY 4, 1905.

J. P. RICHARDSON.

METHOD OF MAKING BRAZED JOINTS.

APPLIGATION FILED MAR. 7, 1904.

no. "reacts.

ftatented July at, 1905.

JOHN F. ltltl llAltDrltlN, Oil .l llhirllrlllltt-f, PIGNLSYLVANJA.

lll 'l llii 'l M lit U P l ll'l r l Ml P ll t3 lit f l at. lit. llfi dtil l l il if'tit SPECIFICATION forming part of Letters Patent No.793,95c, dated July 4t, 1905.

Application filed March 7, 19%. Serial lilo. 196,919.

To all 11171.01 if? 'n'tm (1077156777,:

Be it known that ii, Jenn l1. RIeuAnnsoN, a citizen of the United Statesof J imerica, rcsid ing at Pittsburg, in the county of Allegheny andState of Pennsylvania, have invented certain new and useful lmprovements in M ethods of l rlaking Brazed Joints, of which thefollowing is a specification, reference being had therein to theaccompanying drawings.

This invention has relation to a method of making brazed joints, andhas'for its object the provision of a novel method of and means forsecuring a perfect brazing of joints in certain classes of metals whichit has heretofore been found diflicult to braze in a satisfactorymanner.

My invention is particularly applicable to the brazing of broken jointsin cast-iron or high-carbon steel.

it has heretofore been difficult to make a good brazed joint between twopieces of castiron or higlncarbon steel, particularly where the sectionsto be joined together were broken apart, owing to the fact that thematerial used for brazing would not flow readily and into a close jointor a crack. it is well known that when a piece of metal is broken thematerial on each side of the fracture is to a certain extentdisintegratcd and weakened by the force which produces the fracture, andif, therefore, the pieces be united by brazing them together thematerial will be liable to be again fractured on lines parallel with theoriginal fracture, owing to the weakness of the metal adjacent to thebrazed joint.

in carrying my invention into effect l insert between the adjacent facesof the joint which is to be brazed a thin strip of metal of suchcharacter that the brazing material will [low over its surface andattach itself to the adjacent surfaces of the material to be joined,whereby l secure a perfect adhesion of the brazing material throughoutthe entire surfaces abutting said strip. in addition to the strip ofmetal which i employ as above described i apply to the material to bejoined reinforcing-pieces composed of a material which will serve toeomlnctthe brazing material in the same manner as is done by theaforesaid strip, these rein forcing-pieces crossing the joint orfracture and being socketed in the adjacent sections of the material tobe joined and being brazed th ereto simultaneously with the brazing ofthe joint.

in the accompanying drawings, wherein joints which have been brazedaccording to my method and by means of the devices appertaining theretoare shown, Figure 1. is a side elevation of a gear-wheel in which twoteeth have been removed and replaced by new teeth. lfig. 2 is a planview of a strz'tight bar, showing one form of reinforcing-piece asapplied to a joint brazed by my improved means. Fig. 3 is a plan view ofa link, showing a modilied form of reinforcil1g--pieces. liig. 4L is aplan view of a square frame which has been fractured and brazed at onecorner and showing a further modified form of applying thereinforcing-piece. Fig. 5 is an edge view of the article shown in Fig.l. Fig. (5 is a sectional view of a shaft which has been cracked andbrazed according to my improved method.

The [irst step in my method is to secure a clean surface on the portionswhich are to be brazed, and this l effect either by washing the surfaceswith acid or preferably by abrading by means of a suitable tool, such asa lilo or an emery-wheel, the latter method being preferable asalfording a means for removing the weakened portion of the metaladjacent to the fracture and also widening the fracture, so as toprovide room for the joining-strip and brazing material, so as to makethe joint without lengthening the article joined. if the joint is to bemade without the reinforcing piece or pieces, as may sometimes be thecase-as, for instance, where the new teeth are to be inserted in thegear-wheel shown in Fig. 1- l. insert between the pieces 2 3 a strip 1of suitable metal, shaped to conform to the shape of the joint, and lthen braze the parts 2 and 8 to each side of the strip ,1. by means of asuitable flux and a suitable lu'azing material.

in Fig. 2 of the drawings, in which l have shown a joint made in astraight bar, l employ in connection with a joining-strip-t a, reinfercing-piece 5, which is socketed in suitable recesses 6 6 in thepieces 7 8 of the article being brazed, this rein forcing-piece 5 beingmade of material of such character that the brazing material will flowfreely over its surface during the brazingoperation and will tightlybraze it in the recesses 6 6.

ln Fig. 3 of the drawings I have shown a joint running at an angle tothe sides of the two sections 9 10 to be brazed together, and in thiscase 1 have shown reinforcing-pieces ll 12 13, which are let into thesurfaces of the sections 9 10 and cross the fracture at substantiallyright angles, the joining-strip in this figure being lettered 1a, thelatter being properly shaped on its upper edge to admit of the passageof the reinforcing-pieces 11 12 13.

In Fig. i of the drawings 1. hare shown a square frame which has beenfractured at one corner, and in this instance a reinforcingpiece 15 isarranged in a hole bored at an angle to the sides of the frame andthrough the joining-strip l6.

Fig. 5 shows the joining-piece 15 as being located centrally of thesides 1T 18 of the frame; but it may be located in any other desirableposition.

In Fig. 6 I have illustrated a shaft 19, which has been cracked from theperiphery toward the center and in which a joining-strip 20 has beeninserted in the crack.

The brazing material in each figure is designated by the letter B. lheparticular material which 1 prefer to employ for the joiningstrips andfor the reinforcing-pieces is steel, and I find that the best effect isproduced where the steel is coated previously to being inserted in thejoint by some other metal, an excellent material for the strips beinggalvan' ized sheet-steel.

The joint formed in the manner above described is extremely strong, andI have demonstrated in actual practice that such joints render thearticle as strong at the point of fracture as at any other point ofequal area throughout the article, particularly where thereinforcing-pieces above described are employed, for the reason that thereinforcingpieces being of steel are of greater tensile strength thanthe material which has been brazed and which is ordinarily cast-iron orbrittle high-carbon steel.

Having fully described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. The method of making brazed joints consisting in inserting betweenthe abutting surfaces of the parts to be joined a strip of metal coatedwith a metal of different character from said surfaces, and then brazingsaid strip to said surfaces.

2. The method of making brazed joints consisting in abrading thesurfaces to be joined, inserting a strip of metal of different materialfrom the sections to be joined between the abutting surfaces of the sameand then brazing said strip to said surfaces.

3. A method of making brazed joints consisting in inserting between theadjacent surfaces of the article to be brazed a strip of metal ofdiiferent character from the article, and inserting a reinforcing-piecein a recess intersecting the joint, and brazing the said strip and thesaid reinforcing-piece in position.

1n testimony whereof I affix my signature in the presence of twowitnesses.

JOHN F. RICHARDSON.

Nitnesses:

H. (J. EVERT, E. E. POTTER.

